Thousands of tanks are presently in service worldwide for storage of ground water contaminating fluids. Older varieties of these tanks fabricated of steel and unprotected cathodically are subject to internal and external corrosion which will eventually cause leaking of the stored fluid or admittance of ground water into the tank. The rate of corrosion depends on the corrosiveness of the tank support structure or the contained fluid and the tank surface protective coatings. Leakage of these fluids into the ground water constitutes an extreme hazard to the public and environment; and, leakage of ground water into the tank adversely affects the quality of the stored fluid.
Here-to-fore leaking tanks have been replaced with new tanks, repaired in place or abandoned. The cost of replacing all old tanks with new tanks at one time would impose such an economic burden on many operators that they could not remain in business; therefore, tanks are usually replaced only when leaks are detected and many times this detection is made only after considerable contamination has already taken place. Fiberglass epoxy lining materials have been rejected according to information received on rules of the current Uniform Fire Code. Additionally, this in-place repair method cannot be considered a permanent solution since the tank will continue to corrode and there is no positive means to determine that the coating has not developed leaks. Abandonment of leaking tanks results in loss of storage capacity which can only be considered where other adequate storage is available.